Submission #168831

#	Time	Username	Problem	Language	Result	Execution time	Memory
168831		MohamedAhmed04	Mobile (BOI12_mobile)	C++14	90 / 100	1051 ms	8312 KiB

mobile

#include <bits/stdc++.h>
 
using namespace std ;
 
const int MAX = 1e6 + 10 ;
int x[MAX] , y[MAX] ;
int n , l;
double a , b , now;
 
bool check(double radius)
{
	now = 0.00 ;
	for(int i = 0 ; i < n ; ++i)
	{
		a = sqrt(radius * radius - ((-y[i] * 1ll) * (-y[i] * 1ll))) + x[i] * 1ll ;
		b = -sqrt(radius * radius - ((-y[i] * 1ll) * (-y[i] * 1ll))) + x[i] * 1ll ;
		if(a > b)
			swap(a , b) ;
		if(a <= now)
			now = max(now , b) ; 
	}
	return (now >= l) ;
}
 
int main()
{
	ios_base::sync_with_stdio(0) ;
	cin.tie(0) ;
	scanf("%d %d" , &n , &l) ;
	for(int i = 0 ; i < n ; ++i)
		scanf("%d %d" , &x[i] , &y[i]) ;
	double low = 0.000 , high = 1e9 ;
	double ans = high ;
	for(int i = 0 ; i < 45 ; ++i)
	{
		double mid = (low + high) / 2.00 ;
		if(check(mid))
			ans = mid , high = mid ;
		else
			low = mid ;
	}
	return printf("%.6lf\n" , ans) , 0 ;
}

Compilation message (stderr)

mobile.cpp: In function 'int main()':
mobile.cpp:29:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d" , &n , &l) ;
  ~~~~~^~~~~~~~~~~~~~~~~~~
mobile.cpp:31:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d" , &x[i] , &y[i]) ;
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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